Conventionally, in a vehicle, hydraulic oil is used to lubricate and cool an inner portion of an engine and to control an apparatus that is controlled by hydraulic pressure, for example, a valve opening and closing timing control apparatus. A hydraulic oil supply apparatus is employed to supply the hydraulic oil to the inner portion of the engine and the valve opening and closing timing control apparatus, for example. The hydraulic oil is stored at an oil pan when the engine is stopped. When the engine is operated, an oil pump constituting the hydraulic oil supply apparatus is driven. The hydraulic oil in the oil pan is suctioned by the oil pump and discharged to be supplied to the inner portion of the engine and the valve opening and closing timing control apparatus, for example. Because the volume of necessary hydraulic oil for the inner portion of the engine and the valve opening and closing timing control apparatus, for example, changes depending on the number of rotations of the engine, the hydraulic oil supply apparatus may include a configuration that may change the volume of hydraulic oil supplied to the inner portion of the engine or the valve opening and closing timing control apparatus, for example, depending on the number of rotations of the engine. Such the hydraulic oil supply apparatus is described in the following Patent Document 1.
An oil supply apparatus for a vehicle disclosed in Patent Document 1 is configured to include an oil pump driven by a rotation of an engine to discharge oil, a hydraulic actuator (valve opening and closing timing control apparatus) operated by the hydraulic pressure of oil discharged from the oil pump, and an engine lubrication apparatus lubricating each member of the engine by the hydraulic pressure of oil discharged from the oil pump. The oil supply apparatus for the vehicle includes a variable pressurizing valve that restricts a flow volume of oil to the engine lubrication apparatus from the oil pump in a case where the hydraulic pressure is low so as to prioritize oil supply to the hydraulic actuator from the oil pump.